I think the easier way is to use the substitution method and replace the y in the second equation with 7-3x, so the second equation would read: 2x-3(7-3x)=12. After simplifying, you'd have 11x-21=12. Add 21 to both sides to get 11x=33. Divide both sides by 11 to get x=3. Obviously either way works, but you're making larger numbers by multiplying the first equation by 3.
@vincentortega4284
2 жыл бұрын
Hi, I totally agree. I used the substitution method; it works faster. x=3 and y= -2
@cbesthelper404
Жыл бұрын
However, students need to learn this method as well. Teachers know that there are "easier" ways. Students are not enlightening them about that. It's just that the teacher has a specific objective to teach a particular method at times.
@markjakeway20352 жыл бұрын
After many years of every different approach I now use a much more 'sledgehammer' approach approach, I tell them to make sure the x and y (or whatever letters) are aligned, they usually are, then multiply first equation by the first number in the second, then multiply the second equation by the first number in the first. This gets the x's 'equal' then take away or add but it's mostly take away. Going after y in your manner or looking for which variable is easier to eliminate takes too much thought for many. Yes I know understanding goes out the window but I've found that for students getting correct answers (and exam good exam results) beats understanding any day of the week, Understanding may/will come later for those that need it or want it. Heresy I know for some but I've found that success breeds success and nothing is more destructive to loving and developing that love for maths than getting wrong answers all the time.
@benquinneyiii79415 ай бұрын
You make it look easy
@thejoker_19922 жыл бұрын
Just 1 question. Isnt this also called simultaneous equations
@MrMousley9 ай бұрын
Ok, let's have a go before I watch your video ... 3x + y = 7 and 2x - 3y = 12 The first one is the easier one to just say that y = 7 - 3x and then substitute in the second one 2x - 3(7 - 3x) = 12 giving you 2x - 21 + 9x = 12 2x + 9x = 12 + 21 11x = 33 x = 3 and if 3x + y = 7 and x = 3 that means 9 + y = 7 y = 7 - 9 = -2
@walterbrown86942 жыл бұрын
We don't "Solve the System" - We solve for the variables in a system of 2 independent equations with 2 variables.
@cbesthelper404
Жыл бұрын
You solve the system since the single set of solutions satisfies both equations.
Пікірлер: 9
I think the easier way is to use the substitution method and replace the y in the second equation with 7-3x, so the second equation would read: 2x-3(7-3x)=12. After simplifying, you'd have 11x-21=12. Add 21 to both sides to get 11x=33. Divide both sides by 11 to get x=3. Obviously either way works, but you're making larger numbers by multiplying the first equation by 3.
@vincentortega4284
2 жыл бұрын
Hi, I totally agree. I used the substitution method; it works faster. x=3 and y= -2
@cbesthelper404
Жыл бұрын
However, students need to learn this method as well. Teachers know that there are "easier" ways. Students are not enlightening them about that. It's just that the teacher has a specific objective to teach a particular method at times.
After many years of every different approach I now use a much more 'sledgehammer' approach approach, I tell them to make sure the x and y (or whatever letters) are aligned, they usually are, then multiply first equation by the first number in the second, then multiply the second equation by the first number in the first. This gets the x's 'equal' then take away or add but it's mostly take away. Going after y in your manner or looking for which variable is easier to eliminate takes too much thought for many. Yes I know understanding goes out the window but I've found that for students getting correct answers (and exam good exam results) beats understanding any day of the week, Understanding may/will come later for those that need it or want it. Heresy I know for some but I've found that success breeds success and nothing is more destructive to loving and developing that love for maths than getting wrong answers all the time.
You make it look easy
Just 1 question. Isnt this also called simultaneous equations
Ok, let's have a go before I watch your video ... 3x + y = 7 and 2x - 3y = 12 The first one is the easier one to just say that y = 7 - 3x and then substitute in the second one 2x - 3(7 - 3x) = 12 giving you 2x - 21 + 9x = 12 2x + 9x = 12 + 21 11x = 33 x = 3 and if 3x + y = 7 and x = 3 that means 9 + y = 7 y = 7 - 9 = -2
We don't "Solve the System" - We solve for the variables in a system of 2 independent equations with 2 variables.
@cbesthelper404
Жыл бұрын
You solve the system since the single set of solutions satisfies both equations.